基于流固耦合的高压混凝土隧洞衬砌结构配筋研究及应用

Study and Application of Reinforced Concrete Lining Structure of High Pressure Concrete Tunnel Based on Fluid Solid Coupling

当采用面力理论计算新疆阿尔塔什水利枢纽工程的发电引水隧洞的配筋量时,衬砌含筋量巨大,与实际情况不符合。对此,采用岩体弹塑性渗流—应力—损伤耦合模型,将动态变化的体积力施加于整个模型,得出混凝土衬砌应变情况,根据衬砌应力按照现行规范进行限裂配筋。计算得出了围岩、衬砌的渗流场、应力场和相应的水力梯度以及最高外渗水头。结果表明,考虑流固耦合下的高压隧洞衬砌应力小于面力理论计算的成果,且前者计算出的混凝土衬砌配筋量远小于后者的计算结果。研究成果可为类似隧洞设计提供参考。

Due to huge amount of steel lining, the amount of reinforcement calculation for power generation tunnel diversion tunnel of Xinjiang ART water conservancy project obtained by the theory of surface force is not consistent with the actual situation. Therefore, the rock elastic-plastic seepage-stress-damage coupling model was used to determine the strain of concrete lining by imposing the dynamic change of volume force on the whole model. Based on the current speci- fication, lining crack reinforcement was implemented in term of lining stress. The seepage field, stress field and the cor- responding hydraulic gradient and the highest water leakage of the surrounding rock and lining were calculated. The re sults show that the stress of the tunnel lining under the fluid solid coupling is less than the theoretical calculation results of the surface force, and the former of calculation results of concrete lining reinforcement are much smaller than the latter. The research results can provide reference for similar design of high pressure tunnel.